This application is related to copending applications Ser. Nos. 435,331 filed Oct. 19, 1982 now U.S. Pat. No. 4,504,442 and 601,443, filed Apr. 18, 1984, now U.S. Pat. No.4,681,739 the disclosures of which are hereby incorporated herein by reference.
The present invention relates to systems for delivering a gas to a confined chamber and to systems for sterilizing substances and articles and particularly to systems using a sterilizing gas to sterilize articles, for example medical apparatus such as utensils and instruments which may have been contaminated by foreign substances. The system of the present invention can also be used to sterilize non-medical articles and substances, as required. The system of the present invention relates particularly to a gas sterilizing system wherein two components which react to provide sterilizing amounts of a gas are combined in the field by the apparatus of the present invention. This allows the components which react to form the sterilizing gas to be shipped separately, which minimizes the possibility of accidents.
In particular, the present invention relates to a system using chlorine dioxide as the sterilizing gas. Chlorine dioxide gas is both unstable and toxic to humans. For example, chlorine dioxide gas, will, over time, decompose into its constituent parts and accordingly, it cannot be transported easily. It is therefore undesirable to transport chlorine dioxide gas. Moreover, chlorine dioxide gas is somewhat explosive and also has a propensity to undergo catalytic decomposition. The components which react to form chlorine dioxide gas (e.g., sodium chlorite and chlorine gas), however, may be transported relatively easily and reacted on site to provide the sterilizing gas chlorine dioxide.
Prior systems have typically used ethylene oxide gas as a sterilant. For example, the castle 4040 ethylene oxide sterilizer manufactured by Sybron Corporation, Medical Products Division, is an example of such a prior system. Although ethylene oxide has been used as a sterilizing gas in the prior systems, chlorine dioxide is a preferred sterilant.
Furthermore, the systems used in the past have typically been of rather simple design and have not included advanced means for maintaining the reliability of the devices and safeguarding against accidents. Additionally, these systems have not provided a great deal of redundancy so that if a component of the system failed, manual intervention or service personnel was required to correct the failure before the sterilizing process could continue.